A building occupied by, or the group name for, a particular house of a religious order of monks or nuns. The name was originally confined to one of the orders of the Benedictine family (e.g., Cistercian, Carthusian, Trappist). Under the rule of St. Benedict, each abbey is to be regarded as a family unit under the nearly autonomous authority of its abbot. It is now also used for a building once used as an abbey.